Abstract: A method for controlling an engine includes the steps of, in response to a transient operating event, determining a first amount of exhaust gas recirculation (EGR) that if provided to an intake of the engine would avoid turbocharger compressor surge in a turbocharger, determining a second amount of EGR that if provided to the intake would avoid turbocharger compressor choke in the turbocharger, and determining a third amount of EGR that if provided to the intake would avoid engine smoking, and adjusting EGR provided to the intake of the engine in accordance with the determined first, second, and third amounts.

Abstract: Various methods and systems are provided for adjusting a flow of exhaust gas in an exhaust gas recirculation system. In one embodiment, a method for an engine comprises controlling a flow of exhaust gas through an exhaust gas recirculation system of an engine system based on a choke level of a turbocharger. For example, the flow of exhaust gas in the exhaust gas recirculation system may be reduced to within a threshold of a choke level of the turbocharger, in response to an ambient condition.

Abstract: Various methods and systems are provided for controlling air flow in a two-stage turbocharger. In one example, an engine method comprises adjusting one or more exhaust gas recirculation valves to maintain a first turbocharger within a first air flow range, and adjusting a turbocharger bypass valve to maintain a second turbocharger within a second air flow range.

Abstract: A method of determining fuel limits for an engine includes measuring an actual fuel value for the engine and creating a plurality of engine speed points. The method further includes calculating respective static fuel limit points for each of the engine speed points utilizing the actual fuel value. The static fuel limit points define and limit a rated power of the engine.

Abstract: Various methods and systems are provided for engine operation with a degraded turbocharger. In one embodiment, a method for an engine comprises reducing mass flow through a first turbocharger while continuing engine operation and adjusting operation of a second turbocharger in response to detected degradation of the first turbocharger.

Abstract: Various methods and systems are provided for lowering exhaust gas temperature. In one embodiment, a method comprises increasing an air-to-fuel ratio of an engine in response to an exhaust gas temperature exceeding a threshold temperature value to lower the exhaust gas temperature to a temperature below the threshold temperature value.

Abstract: Various methods and systems are provided for determining a surge level of a compressor. In one embodiment, a method for an engine comprises updating a stored estimate of a surge level of a compressor responsive to detection of a surge event.

Abstract: Various methods and systems are provided for regulating air flow through a two-stage turbocharger. In one embodiment, a method for an engine comprises, in response to a transient engine operating event, adjusting a provided amount of exhaust gas recirculation provided to an intake of the engine based on at least one of desired intake oxygen, one or more turbocharger conditions of a turbocharger, or a magnitude of the transient engine operating event.

Abstract: A method for controlling an engine includes the steps of, in response to a transient operating event, determining a first amount of exhaust gas recirculation (EGR) that if provided to an intake of the engine would avoid turbocharger compressor surge in a turbocharger, determining a second amount of EGR that if provided to the intake would avoid turbocharger compressor choke in the turbocharger, and determining a third amount of EGR that if provided to the intake would avoid engine smoking, and adjusting EGR provided to the intake of the engine in accordance with the determined first, second, and third amounts.

Abstract: A method of determining fuel limits for an engine includes measuring an actual fuel value for the engine and creating a plurality of engine speed points. The method further includes calculating respective static fuel limit points for each of the engine speed points utilizing the actual fuel value. The static fuel limit points define and limit a rated power of the engine.

Abstract: Various methods and systems are provided for determining a surge level of a compressor. In one embodiment, a method for an engine comprises updating a stored estimate of a surge level of a compressor responsive to detection of a surge event.

Abstract: Various methods and systems are provided for adjusting a flow of exhaust gas in an exhaust gas recirculation system. In one embodiment, a method for an engine comprises controlling a flow of exhaust gas through an exhaust gas recirculation system of an engine system based on a choke level of a turbocharger. For example, the flow of exhaust gas in the exhaust gas recirculation system may be reduced to within a threshold of a choke level of the turbocharger, in response to an ambient condition.

Abstract: Various methods and systems are provided for lowering exhaust gas temperature. In one embodiment, a method comprises increasing an air-to-fuel ratio of an engine in response to an exhaust gas temperature exceeding a threshold temperature value to lower the exhaust gas temperature to a temperature below the threshold temperature value.

Abstract: Various methods and systems are provided for engine operation with a degraded turbocharger. In one embodiment, a method for an engine comprises reducing mass flow through a first turbocharger while continuing engine operation and adjusting operation of a second turbocharger in response to detected degradation of the first turbocharger.

Abstract: Various methods and systems are provided for regulating air flow through a two-stage turbocharger. In one embodiment, a method for an engine comprises, in response to a transient engine operating event, adjusting a provided amount of exhaust gas recirculation provided to an intake of the engine based on at least one of desired intake oxygen, one or more turbocharger conditions of a turbocharger, or a magnitude of the transient engine operating event.

Abstract: Various methods and systems are provided for controlling air flow in a two-stage turbocharger. In one example, an engine method comprises adjusting one or more exhaust gas recirculation valves to maintain a first turbocharger within a first air flow range, and adjusting a turbocharger bypass valve to maintain a second turbocharger within a second air flow range.